Commit Graph
10 Commits
Author SHA1 Message Date
Vivian WangandAnup Patel a69eb6cc65 lib: sbi_trap: Set hstatus.GVA when going to HS-mode
The privileged spec specifies that on a trap to HS-mode, hstatus.GVA
should be set to 1 if stval is written with a guest virtual address, and
to 0 otherwise. Implement this by setting hstatus.GVA to trap->gva when
redirecting traps to HS-mode.

Signed-off-by: Vivian Wang <dramforever@live.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-08-22 08:50:23 +05:30
Vivian WangandAnup Patel 5a0ca098f1 lib: sbi_trap: Set hypervisor CSRs for HS-mode
The hypervisor CSRs hstatus, htval, htinst should always be set if the
trap is to be taken in HS-mode, regardless of which mode it came from.

Signed-off-by: Vivian Wang <dramforever@live.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-08-22 08:50:04 +05:30
Vivian WangandAnup Patel 1c4ce74f51 lib: sbi: Set gva when creating sbi_trap_info
In some cases the sbi_trap_info argument passed to sbi_trap_redirect is
created from scratch by filling its fields. Since we previously added a
gva field to struct sbi_trap_info, initialize gva in these cases also.

Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Vivian Wang <dramforever@live.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-08-22 08:49:49 +05:30
Vivian WangandAnup Patel 1fbe7778c9 lib: sbi_trap: Save mstatus[h].GVA in trap->gva
The machine mode GVA field is available if the hypervisor extension is
implemented, and indicates if mtval is a guest virtual address. Add a
gva field to sbi_trap_info for this, and in __sbi_expected_trap_hext,
save mstatus[h].GVA to it, so that gva indicates if tval is a guest
virtual address. If the hypervisor extension is not implemented, always
set gva to 0.

Signed-off-by: Vivian Wang <dramforever@live.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-08-22 08:49:39 +05:30
Vivian WangandAnup Patel 9529e360df include: Add mstatus[h].GVA encodings
The machine mode GVA field is in mstatus for RV64 and mstatush for RV32,
and is available if the hypervisor extension is available. If an
exception occurs, we may need to redirect the trap to HS-mode, in which
case, hstatus.GVA should be set to same as the machine mode GVA bit.

Add MSTATUS_GVA for RV64, MSTATUSH_GVA for RV32, and their SHIFT
encodings. The SHIFT index is helpful in assembly code, since field
extraction can be implemented in only one register. In pseudocode:

- For RV32: gva = (mstatus >> MSTATUS_GVA_SHIFT) & 1;
- For RV64: gva = (mstatush >> MSTATUSH_GVA_SHIFT) & 1;

Signed-off-by: Vivian Wang <dramforever@live.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-08-22 08:49:29 +05:30
dramforeverandAnup Patel b9edf49b67 lib: sbi: Fix printf handling of long long
Read long long arguments directly using va_arg. Remove original hack for
RV32 that read a long long arg as two long args.

This un-breaks the case on RV64 where e.g. the long long is followed by
an odd number of ints:

    sbi_printf("%d %lld", (int) 1, (long long) 2LL);

Also remove the acnt variable, which is now unused.

Signed-off-by: dramforever <dramforever@live.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-07-30 11:55:51 +05:30
dramforeverandAnup Patel a07402ac9c lib: sbi: Fix tval and tinst for sbi_get_insn()
We should not change trap->tval to mepc because mtval already points to
the faulting portion of the emulated instruction fetch, which is also
what stval is expected to be.

In addition, htinst is only allowed to be zero for instruction access
faults or page faults, and is only allowed to be zero or a
psuedoinstruction for instruction guest-page faults. Fix trap->tinst for
these cases.

Signed-off-by: dramforever <dramforever@live.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-06-21 08:31:56 +05:30
dramforeverandAnup Patel 187127fb89 lib: sbi: Fixup tinst for exceptions in sbi_misaligned_*()
If there is an exception while emulating a misaligned load/store, fixup
uptrap.tinst before redirecting. Otherwise, HS-mode software may receive
an htinst describing the lbu/sb instruction that faulted during
emulation[1].

[1]: https://github.com/riscv-software-src/opensbi/issues/258

Signed-off-by: dramforever <dramforever@live.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-06-21 08:31:14 +05:30
dramforeverandAnup Patel 551c70c040 include: sbi: Add mtinst/htinst psuedoinstructions
Add psuedoinstruction encodings written to mtinst/htinst for faults
caused by implicit memory access for VS-stage address translation

Signed-off-by: dramforever <dramforever@live.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-06-21 08:31:04 +05:30
dramforeverandAnup Patel adc3388d76 lib: sbi_trap: Redirect exception based on hedeleg
HS-mode software can choose what exceptions to delegate to VS-mode using
the hedeleg CSR. Synthetic VS/VU-mode exceptions should also honor
hedeleg. They should be redirected to VS-mode if and only if delegated
by HS-mode.

Signed-off-by: dramforever <dramforever@live.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-06-13 11:02:49 +05:30